Multilocus sequence typing system for Campylobacter jejuni - PubMed (original) (raw)

Multilocus sequence typing system for Campylobacter jejuni

K E Dingle et al. J Clin Microbiol. 2001 Jan.

Abstract

The gram-negative bacterium Campylobacter jejuni has extensive reservoirs in livestock and the environment and is a frequent cause of gastroenteritis in humans. To date, the lack of (i) methods suitable for population genetic analysis and (ii) a universally accepted nomenclature has hindered studies of the epidemiology and population biology of this organism. Here, a multilocus sequence typing (MLST) system for this organism is described, which exploits the genetic variation present in seven housekeeping loci to determine the genetic relationships among isolates. The MLST system was established using 194 C. jejuni isolates of diverse origins, from humans, animals, and the environment. The allelic profiles, or sequence types (STs), of these isolates were deposited on the Internet (http://mlst.zoo.ox.ac.uk), forming a virtual isolate collection which could be continually expanded. These data indicated that C. jejuni is genetically diverse, with a weakly clonal population structure, and that intra- and interspecies horizontal genetic exchange was common. Of the 155 STs observed, 51 (26% of the isolate collection) were unique, with the remainder of the collection being categorized into 11 lineages or clonal complexes of related STs with between 2 and 56 members. In some cases membership in a given lineage or ST correlated with the possession of a particular Penner HS serotype. Application of this approach to further isolate collections will enable an integrated global picture of C. jejuni epidemiology to be established and will permit more detailed studies of the population genetics of this organism.

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Figures

FIG. 1

FIG. 1

Chromosomal locations of MLST loci. The positions of the seven loci are shown on a map of the C. jejuni chromosome derived from the genome sequence of isolate NCTC 11168 (

http://www.sanger.ac.uk/Projects/C\_jejuni/

). The 1,641,481-bp genome is divided into 10 segments (indicated on the inner circle), with each segment representing 164,148 bp.

FIG. 2

FIG. 2

Allele frequencies in the sample population. For each of the seven loci (A to G), the number of times that each allele occurs in the isolate collection is shown. The frequencies are shown in the order of most to least abundant.

FIG. 3

FIG. 3

Splits graphs showing the interrelationships of members of ST-21 complex. Progressive pruning of branches to improve resolution is indicated by the circles and arrows. The completely resolved region (bottom left) derived from the center of the unpruned graph contains the most abundant members of the complex and the predicted founder of the lineage, ST-21.

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References

    1. Achtman M, Zurth K, Morelli G, Torrea G, Guiyoule A, Carniel E. Yersinia pestis, the cause of plague, is a recently emerged clone of Yersinia pseudotuberculosis. Proc Natl Acad Sci USA. 1999;96:14043–14048. - PMC - PubMed
    1. Adak G K, Cowden J M, Nicholas S, Evans H S. The Public Health Laboratory Service national case-control study of primary indigenous sporadic cases of campylobacter infection. Epidemiol Infect. 1995;115:15–22. - PMC - PubMed
    1. Altekruse S F, Stern N J, Fields P I, Swerdlow D L. Campylobacter jejuni—an emerging foodborne pathogen. Emerg Infect Dis. 1999;5:28–35. - PMC - PubMed
    1. Bolton F J, Surman S B, Martin K, Wareing D R A, Humphrey T J. Presence of Campylobacter and Salmonellae in sand from bathing beaches. Epidemiol Infect. 1999;122:7–13. - PMC - PubMed
    1. Bolton F J, Wareing D R A, Skirrow M B, Hutchinson D N. Identification and biotyping of campylobacters. In: Board R G, Jones D, Skinner F A, editors. Identification methods in applied and environmental microbiology. London, United Kingdom: Blackwell Scientific Publications Ltd.; 1992. pp. 151–161.

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